public class Ex4_25{
	public static void main(String[] args){
		final int i = 100000;
		double s = 1;
		double t = 1;
		double sum = 0;
		for (int j = 0; j <= i; j++){
			sum += s / t;
			s = -s;
			t += 2;
		}
		System.out.printf("%.10f\n", 4*sum);
		System.out.printf("%.10f\n", Math.PI);
	}
}